Improvement in steam-engine governors



.TEREMIAH A. MARDEN, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO CHARLES E.AND IJOHN H. ABBOTT, OF SAME PLACE.

Letters Patent No. 88,497, dated March 30, 1869.

IMPROVEMENT IN STEAM-ENGINE `G-OVERII'OIRS.

The Schedule referred to in these Letters Patent and making part of thesame.

To all whom it may concern:

Be it known that I, JEREMIAII A. MARDEN, of Boston, in the county ofSuffolk, and State of Massachusetts, have invented certain Improvementsin Governors for Steam-Engines, of which the following is a full, clear,and exact description, reference being had to the accompanying drawings,making ,part of this specification, in which- Figure 1 is a perspectiveview of the exterior' of the casing which encloses the valve, witll such4portion of my improvements applied thereto as are situated outside.

of the same, soule of the mechanism being sllown in elevation, thevarious parts being in the position tlley occupy when the valve is wideopen.

Figure 3 is all elevatioll, representing the receptacle which contaillsa portion of lny improvements broken away, to show their construction,the parts being in the posit-ion tlley occupy when the valve is nearlyclosed.

Figure 4 is a section entire line x x of fig. 2.

Figure 5 is a perspective view ofthe extension paddle-blade, with someof the mechanism immediately colnlected therewith.

My invention consists in one or more extension paddie-blades, revolvingin a receptacle containing oil, or other suitable fluid, the increasedresistance on the extension-blade or blades, occasioned by its or theirincreased Aate of speed through the fluid, causing the blade or bladesto be deflected, in such manner as to operate certain devices connectedtherewith, and partially close the valve to the steam-chest, thusreducing the pressure of the steam, and consequently checking I thespeed as required; and, in combination with such extension paddle-bladeor blades,

My invention also consists ill a rocker-shaft, which raises or allows todescend a sliding rod, which servesl as a movable fulcrum for the upperof one` of a series of levers connected with the valve-stem, weigllts ofdifferent denominations being employed, according to the mean degree ofspeed which it is required for the engine to maintain.

To enable others skilled in the art to understand and use lny invention,I will proceed to describe the manner in which I have carried it out.

In the said drawing, the base of the casing A, which encloses thevalve-chamber, is secured to the steamchest of the cylinder, theinduction-passage communicating with the valve-chamber.

The stem of thevalvc passes through the outside of the casing, at a, andhas secured thereto a short bent level', B, to the outer end ofwhich ispivotcd the lower end of an upright level', C, which carries weights, D,of the denomination necessary for maintaining any desired uniform rateof speed predetermined.

The upright level' C passes through a slotted guide, I), and has pivotedto its upper eml the outer end of Figure 2 is a longitudinal sectionthrough the centre all arm,'or lever, Ewhieh rests in a bifurca'tedfulcrum, c, at the uppenend of a vertical rod, F, which passes throughthe top of a receptacle, G, containingoil, the lower eml of thisvertical rod extending down illto the receptacle, and being free toslide up alld down, when acted on by mechanism hereafter to bedescribed.

The inner end of the level' E is pivoted, at ll, to a short stud, O,rising from the top ofthe oil-receptacle, G.

'A horizontal shaft, H, passes .through alld has its bearing in the studO, the outer extremity of the shaft having a drun1,'or pulley, I,secured thereto, while the inner extremity of the shaft carries abevel-wheel, J, which meshes into a bevel-wheel, K, on the top of avertical shaft, or spindle, c, passing through the centre of the top ofthe oil-receptacle G, the shaft ofthe bevel-wheel being hollow at itscentre, to allow the rod F to slide freely up and down therein.

The lower end of the hollow shaft, or spindle e terminates ill acircular flange, or plate, L, which is bent down at points diametricallyopposite, forming two forks, f f, into which the ends of'a short'shaft,g, have their bearings.

One extremity of this short shaft projects outside one of the forkedbearings, alld has secured to it a paddle-blade, M, of a curved form inthe direction of its length, t. c., downward, while it is flat in itshorizontal cross-section.

A sliding sleeve surrounds, or partially surrounds, the paddle-blade L,and forms all extension-piece, N, thereto.

To the lower cud of this extension-piece is pivoted the lower end of astraight rod, h, while the upper end ofthe rod is pivoted, at Ii., 4to aprojection on the under side of the circular flange, or plate L, bywhich construction-the paddle-blme, with its extension, is free to movelongitudinally into an inclined position.

The centre of the shaft q has formed thereon a short arm, 7:, having acup-shaped recess, l, at its outer end, into which the lower end of thevertical rod F rests.

Over the pulley I, and a pulley on the crank-shaft,

- (not shown,) is intended to be passed a belt, by which the motion ofthe engine is communicated, to drive the pulley I, and, through theconnections above described, to revolve the extension paddle-bladearound witllin the oil contained in the receptacle G.

The normal position of the paddle-blade and its extension, when at rest,is that showll ill lig. 2, the lower end of the extension being slightlyabove or even with the bottoln ofthe blade; but, as the valve opens, andsteam is let on, they commence to revolve through the oil, theresistance of which thereto, as the speed of the engine increases,causes the blade and its extension to be deflected, the latter slidingdowll upon its blade, and the outer ,end of the arln k is thrown up,thereby raising the vertical rod F intovthe position shown in lig. A

The ascent of the rod F raises the outer end of the upperl lever, E, andwith it the upright weighted lever C, which, in its turn, brings np theouter end of the lower lever, B, connected with the valve-stem, andcloses the valve sufficiently to shut off a portion ofthe steamnecessary to reduce lche speed to the uniform rate determined on, theextension of the paddleblade sliding up thereon, and the blade itselfapproaching toward the position seen in lig. 2.

To prevent any objectionable flaring ofthe oil, when pressed upon by thepaddle-blade, l provide the receptaole G with a series of projections,on, which serve to keep the surface of the oilcomparatively level, andthus insure the paddle-blade being properly immersed therein.

It will be seen, that when the engine is revolving blade may beconnected to the rocker-shaft H, and other uid than oil may be used inthe receptacle G; but I prefer the use of oil.

. Instead of three levers, B G E, one, only, if properly Claims.

'What I claim as my invention, and desire to secure by Letters Patent,is

The sliding adjustable paddle N and rod 71, substantially as set forth.

Also, in combinationwith the above paddle-blade N, the rocker-shaft g,sliding rod F,- and Weighted lever, for operating the valve,substantially as set forth.

JEREMIAH A. MARDEN.

fitnessesz N. W. STEARNs, L. E. BATCHELLER.

